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Diffstat (limited to 'libavformat/qtpalette.c')
| -rw-r--r-- | libavformat/qtpalette.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/libavformat/qtpalette.c b/libavformat/qtpalette.c new file mode 100644 index 0000000000..666c6b7351 --- /dev/null +++ b/libavformat/qtpalette.c @@ -0,0 +1,116 @@ +/* + * QuickTime palette handling + * Copyright (c) 2001 Fabrice Bellard + * Copyright (c) 2009 Baptiste Coudurier <baptiste dot coudurier at gmail dot com> + * Copyright (c) 2015 Mats Peterson + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <stdio.h> +#include <stdint.h> + +#include "avformat.h" +#include "libavutil/intreadwrite.h" +#include "qtpalette.h" + +int ff_get_qtpalette(int codec_id, AVIOContext *pb, uint32_t *palette) +{ + int tmp, bit_depth, color_table_id, greyscale, i; + + avio_seek(pb, 82, SEEK_CUR); + + /* Get the bit depth and greyscale state */ + tmp = avio_rb16(pb); + bit_depth = tmp & 0x1F; + greyscale = tmp & 0x20; + + /* Get the color table ID */ + color_table_id = avio_rb16(pb); + + /* Do not create a greyscale palette for Cinepak */ + if (greyscale && codec_id == AV_CODEC_ID_CINEPAK) + return 0; + + /* If the depth is 1, 2, 4, or 8 bpp, file is palettized. */ + if ((bit_depth == 1 || bit_depth == 2 || bit_depth == 4 || bit_depth == 8)) { + uint32_t color_count, color_start, color_end; + uint32_t a, r, g, b; + + /* Ignore the greyscale bit for 1-bit video and sample + * descriptions containing a color table. */ + if (greyscale && bit_depth > 1 && color_table_id) { + int color_index, color_dec; + /* compute the greyscale palette */ + color_count = 1 << bit_depth; + color_index = 255; + color_dec = 256 / (color_count - 1); + for (i = 0; i < color_count; i++) { + r = g = b = color_index; + palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b); + color_index -= color_dec; + if (color_index < 0) + color_index = 0; + } + } else if (color_table_id) { + /* The color table ID is non-zero. Interpret this as + * being -1, which means use the default Macintosh + * color table */ + const uint8_t *color_table; + color_count = 1 << bit_depth; + if (bit_depth == 1) + color_table = ff_qt_default_palette_2; + else if (bit_depth == 2) + color_table = ff_qt_default_palette_4; + else if (bit_depth == 4) + color_table = ff_qt_default_palette_16; + else + color_table = ff_qt_default_palette_256; + for (i = 0; i < color_count; i++) { + r = color_table[i * 3 + 0]; + g = color_table[i * 3 + 1]; + b = color_table[i * 3 + 2]; + palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b); + } + } else { + /* The color table ID is 0; the color table is in the sample + * description */ + color_start = avio_rb32(pb); + avio_rb16(pb); /* color table flags */ + color_end = avio_rb16(pb); + if ((color_start <= 255) && (color_end <= 255)) { + for (i = color_start; i <= color_end; i++) { + /* each A, R, G, or B component is 16 bits; + * only use the top 8 bits */ + a = avio_r8(pb); + avio_r8(pb); + r = avio_r8(pb); + avio_r8(pb); + g = avio_r8(pb); + avio_r8(pb); + b = avio_r8(pb); + avio_r8(pb); + palette[i] = (a << 24 ) | (r << 16) | (g << 8) | (b); + } + } + } + + return 1; + } + + return 0; +} |